Unless otherwise indicated herein, the materials described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
Rotary joint devices are typically used for transmission of power and/or electrical signals between one structure and another structure in an electromechanical system that operates by causing a relative rotation between the two structures (e.g., stator and rotor). Example systems that employ rotary joint devices include remote sensing systems (e.g., RADARs, LIDARs, etc.) and robotic systems (e.g., for directing microphones, speakers, other robotic components, etc.), among other possibilities.
A slip ring joint is an example rotary joint device that typically involves a conducting brush disposed in one structure to remain largely in contact with a conducting ring disposed in the other structure as the rotor rotates. Slip ring joints may be associated with high maintenance and/or production costs due to the damaging effect of friction between the brush and the ring as the rotor rotates.
An optical rotary joint is an example rotary joint device that typically involves a light source disposed in one structure to emit modulated light indicative of transmitted data towards a photodetector disposed in the other structure. Optical rotary joints may be associated with data transmission rate limitations due to an extent of possible light modulations that can be uniquely detected by the photodetector.
A radio-frequency (RF) rotary joint is an example rotary joint device that typically involves an antenna disposed in one structure to emit RF electromagnetic waves towards another antenna disposed in the other structure. RF rotary joints may be associated with data transmission rate limitations due to the relative motion between the two antennas as the rotor rotates. By way of example, the relative motion between the two antennas may cause variations in polarizations of the respective antennas, or mismatches between beamforming patterns of the respective antennas, among other possibilities. As a result, the relative rotation between the two structures may affect the quality of wireless communication between the two antennas. Thus, due to the relative rotation between the two structures, the available RF bandwidth for reliable wireless data transmission between the two antennas may be limited.